字幕列表 影片播放 列印英文字幕 [long note] -[Thomas Jenkins] What we're showing today is examples of two types of Photovoltaic systems. In this example, we have a fixed rack configuration. In that, the panels are mounted on some type of rack and the rack is pointed in most cases directly south and it never moves. This is a little bit more sophisticated, in that, it can change the tilt angle which is often good to do because the sun will be at different positions throughout the year. In the winter, it's gonna be lower. In the summer, it's gonna be higher. So your panels will be more efficient if they're pointing directly to the sun. In most cases for home use, this is what you'll use. On the other hand, we have this type of system over here. This is what we call a solar tracker. In this case, this is a passive solar tracker, which means that it works all by itself and it doesn't need any electricity or any motors to work. It all works by simple physics. The tracker will follow the sun from the morning to the evening as it crosses the sky. The panels will collect more of the sun's energy because they're always pointing directly to the sun. The disadvantage of this system is that this is a little bit more expensive. We're gonna get more energy from this system but it's gonna be more expensive to purchase in the beginning. So it'll take a while for that extra energy that you're gonna get every day to pay off in the long run, to pay off the cost of the equipment. So this is a good choice for a lot of systems. In addition, we've mounted a few things that most of homeowners will probably have and these are some devices that allow us to measure voltage and currents, the output from our solar panels. And we can compare the two and see how much of a different energies we get over time. 'Cause that'll convert into how much energy you need for your home because a lot of times homeowners use these to be in a system which is called a grid-tied system, in which they sell energy when they're generating more energy than they use in the home, they sell their excess energy to the electric company. - [Announcer] The preceding was a production of New Mexico State University. The views and opinions in this program are those of the author and do not necessarily represent the views and opinions of the NMSU Board of Reagents.